Adjustable bone stabilizing frame system

ABSTRACT

By providing components securable to anchor pins or screws of different diameters as well as providing clamps which hold associated pins in any position during adjustments, an external fixation or adjustable frame structure is provided which is capable of being quickly and easily assembled in any desired configuration. In the present invention, the frame structure is retained in any assembled configuration in order to allow final adjustments to be made, prior to the final securement of the frame assembly in the precisely desired configuration by closure of each clamp member. In this way, an entire frame assembly is capable of being constructed, adjusted, and readjusted in order to assure each component is oriented in the precisely desired position prior to final closure of the clamping members. In one preferred embodiment, the clamping members employed in the frame structure of the present invention incorporate friction pins internally mounted in each clamp which engages the rod member once this rod is inserted into the jaws of the clamp. In this way, any rod member inserted into the clamping jaws contacts the surface of the jaws and the friction pin, preventing the rod member from sliding or moving relative to the clamp. In addition, by incorporating a uniquely constructed, moving wedge plate that is adjustably engageable with any cooperating anchor pin, secure affixation of the mounting member with the anchor pins of any diameter is easily achieved, regardless of the orientation configuration, or diameter of the anchor pin.

This application is a continuation of application Ser. No. 09/757,912,filed on Jan. 10, 2001, entitled Adjustable Bone Stabilizing Frame,which application is hereby incorporated herein by reference.

TECHNICAL FIELD

This invention relates to external fixation or adjustable bonestabilizing frame systems and, more particularly, to frame assembliesemployed with broken and/or fractured bones for retaining and holdingthe bone and in a desired configuration for resetting.

BACKGROUND

The use of external fixation or stabilizing frames for retaining brokenor fractured bones in a particularly desired orientation orconfiguration is widely known and commonly employed. However, in mosttypical prior art external frame constructions, particularly frameconstructions employed to stabilize broken or fractured bones, a varietyof clamps and holding rods are employed to enable the surgeon toposition the broken/fractured bones in a precisely desired position ororientation, and then allowing the bone to be retained in that positionor orientation for healing.

Although wide variety of frame structures and clamp systems have beenused for this purpose, one common problem existing with most prior artstabilizing frame constructions is the inability to allow the frameconstruction to be easily adjustable during its assembly. In thisregard, in most applications, anchor pins or anchor screws are mountedin a fractured bone, extending outwardly therefrom for attachment to aframe assembly. Clamp members are mounted to the anchor pins or anchorscrews with a plurality of rod members being mounted to a plurality ofinterconnecting clamps to establish the desired stabilizing frameassembly. However, during the creation of the frame structure, whichmust be maintained in a precise orientation in order to assure that thebone fracture is precisely aligned for healing, these prior art framesystems have been found to be incapable of being retained in a desiredposition unless securely clamped. As a result, repeated tightening andloosening of the clamps is required before the precisely desired framestructure is fully assembled.

In those instances where the frame assembly being created has aninsufficient clamping force applied to the rod members for securing therod members in the clamp, slippage of the rod in the clamp often occurs.This causes the frame structure to become improperly aligned, resultingin repeated efforts to recreate and readjust the frame.

In addition, since improper alignment may cause the bone elements to bedislodged from the desired position or may impose improper forces uponthe bone elements, the slippage caused by loose rods cannot betolerated. As a result, the arduous task of clamping and unclampingevery interconnection must be imposed upon the physician, in order toassure a frame structure is created having the precisely desiredconfiguration and orientation and is maintained in that positionthroughout its assembly.

In an attempt to satisfy this need, some clamp members incorporate coilsprings to prevent slippage. However, these systems do not provide thedesired result and are expensive to produce.

Therefore, it is a principal object of the present invention to providean adjustable frame structure for stabilizing broken or fractured boneswhich is capable of being the easily constructed by attaching twoanchoring pins or screws, with all compounds thereof being retained inany desired position, without the application of final clamping forces.

Another object to the present invention is to provide an adjustableframe structure having the characteristic features described above whichallows case of assembly while still assuring secure, clampedinterengagement of all components when required.

Another object of the present invention is to provide an adjustableframe structure having the characteristic features described above whichautomatically incorporates friction engagement between slidingcomponents for maintaining such component in any position withoutrequiring a clamping force.

Other and more specific objects will impart the obvious and will impartappear hereinafter.

SUMMARY

By employing the present invention, all of the difficulties anddrawbacks found in the prior art arc eliminated and a fully externalfixation or adjustable frame structure is provided which is capable ofbeing quickly and easily assembled in any desired configuration. Inaddition, the frame structure of the present invention is retained inany assembled configuration in order to allow final adjustments to bemade, prior to the final securement of the frame assembly in theprecisely desired configuration by closure of each clamp member. In thisway, an entire frame assembly is capable of being constructed, adjusted,and readjusted in order to assure each component is oriented in theprecisely desired position prior to final closure of the clamp beingmembers.

In order to attain this previously unrealized goal, the clamping membersemployed in the frame structure of the present invention incorporatefriction pins internally mounted in each clamp which engages the rodmember once this rod is inserted into the jaws of the clamp. In thisway, any rod member inserted into the clamping jaws contacts the surfaceof the jaws and the friction pin. This contact prevents the rod memberfrom sliding or moving relative to the clamp. As a result of thisfriction engagement, the rod member is retained in any position relativeto the clamping jaws, once the rod member has been inserted into thejaws of the clamp.

By employing the present invention, a frame assembly is quickly ineasily constructed in the overall desired configuration with every rodmember and clamp being retained in the position originally placed. Oncethe basic frame structure has been created, final adjustments can beeasily made by moving the rod members relative to the clamping jaws,with complete assurance that unwanted slippage will not occur. Once thefinal configuration has been obtained, each clamp is closed to securelyengage the jaws of the clamp with the rod member, thereby assuring thecreating of an external fixation assembly or frame structure having aprecisely desired configuration for imparting the desired beneficialresults.

In addition, the external fixation system or frame assembly of thepresent invention incorporates components capable of being secured toanchor pins or screws having a wide variety of diameters. Byincorporating a uniquely constructed, moving wedge plate that isadjustably engageable with any cooperating anchor pin, secure affixationof the mounting member with the anchor pins is easily achieved,regardless of the orientation configuration, or diameter of the anchorpin.

The invention accordingly comprises the features of construction,combination of elements and arrangement of parts which will beexemplified in the constructions hereinafter set forth, and the scope ofthe invention will be indicated in the claims.

BRIEF DESCRIPTION OF THE DRAWINGS

For a fuller understanding of the nature and objects of the presentinvention, reference should he had to the following detailed descriptiontaken in connection with the accompanying drawings, in which:

FIG. 1 is a side elevation view depicting one embodiment of a fullyassembled external fixation bone stabilizing frame system of the presentinvention securely mounted for stabilizing a broken tibia;

FIG. 2 is a partially exploded perspective view of one embodiment of apin clamping/mounting member forming one component of the frame systemof the present invention;

FIG. 3 is a partially exploded perspective view of an alternateembodiment of a pin clamping/mounting member employed in the framesystem of the present invention;

FIG. 4 is a partially exploded perspective view of a further alternateembodiment of a pin clamping/mounting member of the present invention;

FIG. 5 is a top plan view of the pin clamping/mounting member of FIG. 4;FIG. 6 is a cross-sectional side elevation view taken along line 6-6 ofFIG. 5;

FIG. 7 is a rear view of the pin clamping/mounting member of FIG. 4;

FIG. 8 is a cross-sectional plan view of the pin clamping/mountingmember taken along line 8-8 of FIG. 7;

FIG. 9 is an exploded perspective view of one embodiment of a clampassembly employed in the frame system of the present invention;

FIG. 10 is a side elevation view of the clamp assembly of FIG. 9 shownfully assembled;

FIG. 11 is a cross-sectional side elevation view of the clamp assemblyof FIG. 10;

FIG. 12 is an exploded perspective view of another embodiment of a clampassembly of the present invention;

FIG. 13 is a side elevation view of the clamp assembly of FIG. 12 shownfully assembled;

FIG. 14 is an exploded perspective view of a further alternateembodiment of a clamp assembly of the present invention;

FIG. 15 is a perspective view depicting an alternate embodiment of afully assembled external fixation bone stabilizing frame system of thepresent invention securely mounted for stabilizing a broken finger bone;

FIG. 16 is an exploded perspective view of one embodiment of a pinclamping/mounting member employed in the frame system of FIG. 15;

FIG. 17 is an exploded perspective view of an alternate embodiment of apin clamping/mounting member of the present invention;

FIG. 18 is an exploded perspective view of a further alternateembodiment of the pin clamping/mounting member of the present invention;

FIG. 19 is a top plan view of the pin clamping/mounting member of FIG.16;

FIG. 20 is a cross-sectional side elevation view of the pinclamping/mounting member of the present invention taken along line 20-20of FIG. 19;

FIG. 21 is a rear view of the pin clamping/mounting member of thepresent invention_(;)

FIG. 22 is a cross-sectional plan view of the pin clamping/mountingmember of the present invention taken along line 22-22 of FIG. 21;

FIG. 23 is an exploded perspective view of a still further alternateembodiment of a clamp assembly of the present invention employed in theframe system of this invention; and

FIG. 24 is a side elevation view of the clamp assembly of FIG. 23depicted fully assembled.

DETAILED DISCLOSURE

By referring to FIGS. 1-24 along with the following detailed discussion,the construction and operation of the external fixation or adjustableframe system of the present invention can best be understood. Althoughthe following disclosure fully details different embodiments of thepresent invention, these embodiments are provided as preferred examplesof the present invention. Consequently, it is to be understood thatthese embodiments are provided for exemplary purposes only, and are notintended as a limitation of the present invention.

In FIG. 1, one embodiment of the external fixation or adjustable framesystem 20 of the present invention is depicted, securely mounted tobroken leg bone 21 or a tibia for maintaining the components of thebroken bone in the precisely desired position for healing. As depicted,leg bone 21 has a transverse break, forming upper part 22 and lower part23.

In order to set and maintain bone 21 in the desired configuration forhealing, anchor pins 24 and 25 are mounted in upper part 22, whileanchor pins 26 and 27 are mounted in lower part 23. In each instance,the anchor pin is securely affixed to the bone element and extendsoutwardly therefrom. Using these externally extending anchor pins, framesystem 20 is created to form an external fixation frame system whichsecures and holds parts 22 and 23 of bone 21 in interconnectedengagement with each other in order to promote complete healing thereof.

One principal component employed in the external fixation frame systemof the present invention is pin clamping and mounting member 30. As ismore fully detailed below, pin clamping/mounting member 30 mayincorporate one or two connecting rods 31, with one or two connectingrods 31 being mounted at opposite ends or substantially mid-way alongthe length of mounting member 30. In the embodiments depicted in FIG. 1,mounting member 30 secured to upper part 22 of bone 21 comprises tworods 31 extending from opposite ends thereof, while mounting member 30affixed to lower part 23 comprises two rods mounted midway along thelength of member 30.

Regardless of the position or number of connecting rods 31 mounted topin clamping/mounting member 30, the overall construction ofclamping/mounting member 30 is substantially identical. In order to bestunderstand this construction, reference should be made to FIGS. 2, 3 and4, wherein these alternate embodiments are depicted, as fully detailedbelow. In addition, reference should also be made to FIGS. 5-8, whereindetails of construction are shown.

In the preferred construction, pin clamping/mounting member 30incorporates a generally rectangular shaped housing with four separateand independent pin receiving cavities 32, 33, 34, and 35 formedtherein, extending from the top surface of the housing to the bottomsurface. In addition, as is more fully detailed below, each pinreceiving cavity 32, 33, 34, and 35 preferably comprises a generallyrectangular or square cross-sectional shape.

Furthermore, a screw receiving cavity 36 is formed adjacentpin-receiving cavities 32 and 33, while screw receiving cavity 37 isformed adjacent pin receiving cavities 34 and 35. In addition, screwreceiving cavities 36 and 37, and pin receiving cavities 32, 33, 34, and35 all extend from the top to the bottom of the housing, with all axesthereof being substantially parallel to each other.

In addition, two elongated slots 38 and 39 are formed in one sidewall ofthe housing forming pin clamping/mounting member 30. Preferably, eachslot 38 and 39 extends into the interior of the housing, through theaxes formed by one of the screw receiving cavities and terminating atthe axis of the adjacent pin receiving cavities. In this way, slot 38extends from one side of member 30 through screw receiving cavity 36 andpin receiving cavities 32 and 33 while slot 39 extends from the sidewall of member 30 through screw receiving cavity 37 and pin receivingcavities 34 and 35. However, slots 38 and 39 do not extend completelythrough member 30 to its opposed side wall.

In completing the principal construction of pin clamping/mounting member30, clamping plates 40 and 41 are employed and constructed for slidingengagement in slots 38 and 39 with locking wedges 42 and 43 controllablyengaged with clamping plates 40 and 41. As depicted, clamping plate 40is inserted in slot 38 for translational movement therein, with lockingwedge 42 centrally engaged with plate 40 for moving plate 40 in slot 38.Similarly, clamping plate 41 is inserted in slot 39 for translationalmovement therein with locking wedge 43 cooperatively associatedtherewith for controlling the movement of late 41 in slot 39.

Locking wedge 42 is mounted in the base of screw receiving cavity 36 andconstructed for being threadedly engaged with movement control screw 44.Similarly, locking wedge 43 is mounted in the base of screw receivingcavity 37 and constructed for threaded engagement with movement controlscrew 45. By employing this construction, rotation of screws 44 and 45in a first direction draws locking wedges 42 and 43 into pinclamping/mounting member 30, while rotation of screws 44 and 45 in theopposite direction causes locking wedges 42 and 43 to be forcedoutwardly from member 30.

In order to provide secure affixation of pin clamping/mounting member 30with the anchor pins inserted into the bone being stabilized, clampingplates 40 and 41 are preferably constructed within a substantiallyC-shape, with center portions 50 and legs 51 and 52 extending therefrom.Preferably, the outside wall of center portion 50 incorporates aplurality of longitudinal ribs 53 formed therein and extendingsubstantially parallel to each other.

In addition, a cam slot 54 is formed in the inside wall of legs 51 and52, with cam slots 54 of each leg being in juxtaposed, spaced,cooperating relationship with each other Furthermore, cam slots 54 areslanted and positioned for cooperating engagement with camming flanges55, as detailed below.

order to control the movement of plates 40 and 41, locking wedges 42 and43 each comprise camming flanges 55 formed on the outside walls thereof,positioned for cooperative, aligned, controlling engagement with camslots 54 of each clamping plate 40 and 41. By employing thisconstruction, rotation of screws 44 and 45 in a first direction, whichcauses wedges 42 and 43 to move into member 30, also causes cammingflanges 55 to advance upwardly in cam slots 54, forcing clamping plates40 and 41 to advance in slots 38 and 39 towards pin receiving cavities32, 33, 34, and 35. By controlling the slope angle employed in formingcam slots 54 and camming flanges 55, the rate of movement of clampingplates 40 and 41 in slots 38 and 39 is precisely controlled.

Furthermore, in the preferred embodiment, spring means 56, in the formof a coil spring, is inserted in slots 38 and 39 in biasing engagementwith center portion 50 of clamping plates 40 and 41. Preferably, asshown in FIG. 6, spring means 56 is retained in cavity 57 formed in pinclamping/mounting member 30. In this way, clamping plates 40 and 41 arecontinuously urged out of pin clamping/mounting member 30 preventingbinding of clamping plates 40 and 41 with anchor pin 24 when removal isdesired. In addition, spring means 56 continuously biases clampingplates 40 and 41 away from pin receiving cavities 32, 33, 34 and 35,thereby facilitating the easy entry of the desired anchor pins into pinreceiving cavities 32, 33, 34, and 35.

By employing the construction detailed above, clamping/mounting member30 is quickly and easily secured to any desired anchor pins. Using theassembly depicted in FIG. 1, one pin clamping mounting member 30 ismounted to upper part 22 of bone 21 by telescopically advancing pin 24through cavity 32 or 33, while also advancing pin 25 through cavity 34or 35. Then, secure affixation of pin clamping/mounting member 30 toanchor pins 24 and 25 is easily achieved by rotationally advancingscrews 44 and 45 into member 30, causing locking wedges 42 and 43 to bedrawn into member 30.

As detailed above, the upward movement of wedges 42 and 43 causesclamping plates 40 and 41 to be advanced in slots 38 and 39 towardsanchor pins 24 and 25. This movement brings the front wall of centerportion 50 of plates 40 into contact with pin 24, while the front wallof center portion 50 of plate 41 contacts pin 25. The rotation of screws44 and 45 continue until pins 24 and 25 are lockingly engaged withplates 40 and 41. By employing ribs 53 on the surface of the front wallof center portion 50, slippage is prevented and secure locked engagementof member 30 with anchor pins 24 and 25 is assured.

Using a virtually identical procedure, pin clamping/mounting member 30is secured to pins 26 arid 27 which are mounted to lower part 23 of bone21. Once plates 40 and 41 have been advanced into secure, abutting,frictional engagement with anchor pins 26 and 27, as detailed above,member 30 is securely affixed to anchor pins 26 and 27, as well as lowerpart 23.

As shown in FIGS. 2, 3, and 4, each of the alternate configurations ofpin clamping/mounting member 30 preferably incorporates pin receivingcavities which comprise a substantially rectangular or square-shapedcross-section. Although any desired shape may be employed, this squareor rectangular shape is preferred in order to enable a wide variety ofanchor pins to be easily receiving therein. In this way, anchor pinshaving varying diameters or shapes are able to be inserted into the pinreceiving cavities and secured therein by abutting, sandwichingengagement between the wall of the cavity and the leading edge orsurface of the center portion 50 of clamping plates 40 and 41.

In addition, as depicted in these Figures, each pin clamping/mountingmember 30 comprises four separate pin receiving cavities 24, 25, 26, and27. Although any desired number of cavities may he employed, fourcavities are preferred for providing substantial universality.

In most procedures involving larger bones, two or four anchor pins aremounted in the bone part for use in stabilization. As a result,regardless of which number of pins are used, pin mounting/clampingmember 30 of this invention may be employed. By employing theconstruction detailed above, each clamping plate 40 and 41 is broughtinto abutting, locking engagement with the anchor pins, regardless ofwhether one or two pins are present. As a result, universal, secure,affixation of pin clamping/mounting member 30 to the desired bone partis attained.

As discussed above in reference to FIG. 1, pin clamping/mounting member30 affixed to upper part 22 of bone 21 incorporates two connecting rods31 extending from opposite terminating ends thereof. Each of theseconnecting rods 31 are employed for securely affixing member 30 andupper part 22 of bone 21 to the remainder of the external fixation frameassembly 20 of this invention.

As depicted in FIG. 1, broken parts 22 and 23 of leg bone 21 are securedand maintained in the desired position for healing by securelyinterconnecting the two pin clamping/mounting members 30 to each otherby clamps 60 and stabilizing rods 61. As detailed below, once this frameassembly is completed, upper part 21 and lower part 22 are securelymounted to each other in abutting, contacting, slip-free engagement inorder to enable complete healing to be achieved.

In order to form frame assembly 20, a clamp assembly 60 is affixed toeach connecting rod 31 of each pin clamping/mounting member 30, whilealso securely affixing a portion of a stabilizing rod 61 in each clampassembly 60. In achieving this result, in accordance with the presentinvention, clamp assembly 60 is preferably constructed in the mannerdepicted in FIGS. 9, 10, and 11.

As shown therein, clamp assembly 60 preferably comprises two separateand independent clamp members 64, each of which comprise a generallyC-shape clamping zone 65, with movement control plates 66 and 67extending from each terminating end of C-shaped clamping zone 65. Inorder to assure that clamp assembly 60 is able to be employed forinterconnecting two stabilizing rods 61 or connecting rods 31 in anydesired angular position relative to each other, each clamp member 64 isarcuately pivotally movable relative to the other into any desiredangular relationship. This construction and operation is furtherdetailed below.

In the preferred construction, clamp member 64 incorporates a co-axiallyaligned screw receiving cavity 68 extending through each plate. Inaddition, each movement control plate 67 of each clamp member 64comprises a circular shaped tooth array formed in the outer surfacethereof, with the pattern of the tooth array being constructed formating interengagement with each other. As depicted, each clamp assembly60 comprises two clamp members 64, with the tooth array of each movementcontrol plate 67 of each clamp member 64 being mounted in cooperatinginterengagement with each other.

In order to maintain clamp members 64 in the desired assembled position,as well as control the secure clamping engagement of clamping zone 65with the rod member mounted therein, clamp assembly 60 incorporates aclamping control screw 70 which extends through each of the receivingcavities 68 formed in each control plate 66 and 67 of each clamp member64.

In the preferred embodiment, screw receiving cavity 68 of each movementcontrol plate 66 comprises screw threads formed therein for threadedengagement with threaded zone 71 of screw 70. In addition, in thepreferred construction, clamping control screw 70 comprises threadedzone 71 formed at its distal end, with head portion 72 formed at itsproximal end. Radially extending flange 73 is also formed on screw 70,directly adjacent head portion 72. Finally, shank portion 72 extendsfrom flange 73 to threaded zone 71 and preferably comprises a generallysmooth outer surface having a diameter for passing through cavity 68 ofcontrol plates 66 and 67.

In the preferred assembled construction; a washer 75 is mounted aboutscrew 70 between flange 73 and the outer surface of control plate 66 forassuring that complete controlled movement of control plates 66 and 67is attained. Finally, an enlarged handle 76 is mounted about headportion 72 in contact with flange 73 for providing controlled rotationalmovement of screw 70 to achieve small or incremental clampingadjustments.

When fully assembled, clamp member 64 are mounted to each other in asubstantially vertically stacked position with the circular tooth arrayof each movement control plate 67 interengaged with the other. Inaddition, this position is maintained by telescopically insertingclamping control screw 70 through the screw receiving cavity 68 of eachof the control plates 66 and 67 of each clamp member 64 until flange 73and head 72 of screw 70 is engaged with the outside surface of controlplate 66 of the upper clamp member 64, while threaded zone 71 of screw70 is threadedly engaged with the screw threads formed in receivingcavity 68 of control plate 66 of the lower clamp member 64.

Once fully assembled, the arcuate rotation of clamping control screw 70in a first direction causes screw 70 to be telescopically advancedthrough cavities 68. However, once flange 73 contacts washer 75 and/orthe outer surface of control plate 66 of upper clamp member 64, anyfurther rotation of screw 70 causes movement control plates 66 and 67 ofeach clamp member 64 to be advanced towards each other by compressingagainst the spring force provided by C-shaped clamping zone 65.Furthermore, this movement causes the clamping diameter of C-shaped zone65 to be reduced, effectively securing a rod member inserted therein.

As is evident from the foregoing detailed discussion, only control plate66 of the lower clamping member 64 is threadedly engaged with screw 70,since the remainder of shank portion 74 is smooth. As a result, therotational movement of screw 70 effectively controls the tightening ofclamp members 64 as well as the loosening of clamp member 64, whendesired, by rotating screw 70 in the opposite direction.

By employing this construction, clamp members 64 of clamp assembly 60are able to be arcuately pivoted relative to each other about the axisdefined by control screw 70. As a result, any desired connecting rods 31and/or stabilizing rods 61 are securely affixed to each other in anyrequired angular relationship. In this way, frame assembly 20 is quicklyand easily created in the precisely desired configuration andorientation.

In order to enhance the arcuate movement and precision placement ofclamping 64 relative to each other, clamp assembly 60 of the presentinvention incorporates bushing 80 which is mounted in and extendsbetween screw receiving cavities 68 of each control plate 67 of bothupper and lower clamp members 64. By incorporating bushing 80 andconstructing bushing 80 to extend between both clamp members 64, theprecise vertical alignment of the clamp members is maintained,regardless of the clamp forces being imposed thereon.

In most prior art clamp assemblies, tilting or pivoting of one clampmember relative to the other often occurs when the clamping forces areimposed. As a result, precise arcuate positioning of the clampingmembers relative to each other is not attainable. However, byincorporating bushing 80, this prior art inability is overcome and anydesired precision arcuate alignment and positioning is achieved.

An additional benefit provided by this construction of the presentinvention is the ability to incorporate a circular tooth array on theface of each control plate 67 which provides extremely fine teeth andgrooves, unattainable with prior art systems. In this way, cooperatingclamp members 64 are able to be fine tuned into precise arcuate relativepositions, thereby assuring the creation of frame assembly 20 which isoptimized in every respect.

Another important feature provided by clamp assembly 60 of the presentinvention is the incorporation of friction means in clamping zone 69 ofeach clamp jaw 65 of each clamp member 64. By providing this uniquefeature, any connecting rod 31 or stabilizing rod 61 positioned inclamping zone 69 is retained in the set position, until moved by thesurgeon. As a result, assembly and adjustments of the external fixationframe assembly 20 are able to be made easily and conveniently, withoutany slippage or movement of the rods in the clamps.

Although alternate constructions may be employed without departing fromthe scope of this invention, the preferred constructions for providingfriction means in clamp assembly 60 is depicted in FIGS. 9, 10, and 11.In this preferred embodiment, each clamping member 64 incorporatesco-axially aligned pin receiving cavity 81 extending through controlplates 67 and 66. Preferably pin receiving cavity 81 is positioned inclose proximity to C-shaped clamping jaws 65, with the axis thereofbeing parallel to the axis of screw receiving cavity 68.

This preferred embodiment is completed by providing an elongatedfriction pin 82 and telescopically inserting and securing friction pin82 in elongated cavity 81. By properly mounting and positioning frictionpin 82 in the manner detailed above, friction pin 82 extends betweencontrol plates 66 and 67, with intermediate portion 83 of the shaft ofpin 82 extending into clamping zone 69. By employing this construction,any connecting rod 31 and/or stabilizing rod 61, which comprises adiameter for being secured in C-shaped clamping jaws 65, will contactintermediate portion 83 of friction pin 81 whenever mounted in C-shapedclamping jaw 65.

As a result, when connecting rod 31 and/or stabilizing rod 61 isinserted into C-shaped clamping jaw 65, intermediate portion 83 offriction pin 82 is flexed away from clamping zone 69, while beingmaintained in frictional engagement with the rod due to the inherentspring force of in 82 attempting to return to its normal straightconfiguration. In this way, a constant frictional engagement force ismaintained on any connecting/stabilizing rod inserted into C-shapedclamping jaw 65, forcing the rod into contact with the surface of jaw65.

This biasing force must be overcome when telescopically inserting andadvancing any connection rod 31 and/or stabilizing rod 61 in C-shapedclamping jaw 65. However, whenever a desired relative position isattained, no clamping adjustment needs to be made. Instead, the biasingforce and frictional engagement of pin 82 with the rod member and thewalls of jaw 65 is sufficient to maintain the rod member in the setposition.

By employing this construction, any desired construction for frameassembly 20 is quickly and easily achieved and fully completed in aninitial orientation, with complete assurance that slippage or sliding ofthe components will not occur, even though secure tightening of eachclamp member 64 has not been attained. In this way, the presentinvention allows the surgeon to fine tune or adjust frame assembly 20 inorder to achieve a precision construction. However, throughout theentire adjustment process, secure clamping is avoided since friction pin82 of each clamp member 64 provides the desired securement of any rodmember in any position during the adjustment process.

Once all of the components of frame assembly 20 have been placed intheir precisely desired position and orientation, each rod member issecurely clamped in jaw 65 of each clamping member 64. Since secureclamping forces are only required when the final configuration of frameassembly 20 has been completed, the construction and adjustment of frameassembly 20 is achieved with substantially enhanced ease, simplicity,and convenience.

As best seen in FIGS. 9 and 11, friction pin 82 comprises an enlargedhead 84 which has a diameter greater than intermediate portion 83. Inaddition, pin receiving cavity 81 is constructed to receiving and retainenlarged head 83 of pin 82.

In the preferred embodiment, the head receiving portion of cavity 81 isformed in control plate 67 of each clamp member 64. As shown, convenientlocation for cavity 81 with the head receiving portion thereof is alongthe tooth and groove array of plate 67. This location and position ispreferred since the tooth/groove array of each control plate 67 ismaintained in abutting, contacting interengagement with the tooth/groovearray of the adjacent control plate 67 of the adjacent clamp member 64.

As a result, positive securement of friction pin 82 in cavity 81 isprovided and any possibility of dislodgement or movement of pin 82 isprevented. In this way, assurance is provided that friction pin 82 isalways present in clamping zone 69 in order to provide the desiredslip-free, fully retained assembly benefits of the present invention.

In FIGS. 12 and 13, an alternate embodiment of clamp assembly 60 isdepicted. In _(t)his embodiment, two separate and independent clampmembers 90 are mounted in a vertically stacked array, as detailed above.However, in this embodiment, each clamp member 90 comprises separate andindependent clamping jaws 91 and 92. In certain applications, telescopicentry into the clamping jaw is not possible, as is required in C-shapedclamping jaw 65. Consequently, two separate and independent clampingjaws 91 and 92, as depicted in FIGS. 12 and 13, are employed whichenable any desired connecting rod 31 and/or stabilizing rod 61 to beinserted into jaws 91 and 92 with ease and simplicity.

In this embodiment, each clamp member 90 comprises a movement controlplate 93 which is interconnected with jaw 91 and a movement controlplate 94 which is interconnected with jaw 92. Movement control plates 93and 94 are positioned in juxtaposed, spaced, vertically aligned,cooperating relationship with each other, enabling clamping jaws 91 and92 to operate in the desired manner.

In order to provide clamping jaws 91 and 92 with the desired, integratedspring biasing force, clamp member 90 also comprises an interconnectingwall member 95 which extends between movement control plates 93 and 94on the side thereof opposite clamping jaws 91 and 92. In this way, anintegrated spring force is provided to clamping jaws 91 and 92 whichtends to open jaws 91 and 92, unless counter-acted by a closing orclamping force.

The remainder of the construction of clamp member 90 is substantiallyequivalent to the construction of clamp assembly 60 as detailed above.In this regard, screw or boss receiving cavities 68 are formed inmovement control plates 93 and 94, with threaded zones being formed incavities 68 of control plate 93, and a smooth boss receiving zone beingformed in cavity 68 of control plate 94. In addition, as detailed above,the top surface of control plate 94 of each clamp member 90 comprises acircular array of teeth and grooves, for enabling the desired mating,interengagement and arcuate rotational movement of each clamp member 90relative to the other clamp member 90.

In addition, bushing 80 is employed for mounted interengagement betweenmating control plates 94 by inserting bushing 80 in cavities 68 of eachcontrol plate 94. In this way, as detailed above, tilting or skewing ofclamp members 90 relative to each other during the clamping process isprevented.

In addition, clamping control screw 70 is telescopically insertedthrough screw receiving cavities 68 of each movement control plate 93and 94 with threaded zone 71 of control screw 70 being engaged incavities 68 of the lower-most control plate 93. In addition, withclamping control screw 70 incorporating head 72, flange 73, shankportion 74 and washer 75, all as described above, any arcuate rotationof control screw 70 in a first direction causes jaws 91 and 92 of eachclamping member to advance toward each other, securely engaging andlockingly retaining any rod member inserted therebetween. In addition,as detailed above, handle 76 may be mounted, if desired, to head 72 ofscrew 70 in order to enable precise, controlled, rotational movement ofscrew 70.

Although constructions of this general nature have been employed in theprior art, all of these prior art constructions suffer from the commondeficiency that any interconnecting wall member 95 is capable of beingcrushed by excessive clamping forces imposed thereon. In such instances,the resulting clamp is incapable of being used.

In the present invention, a unique construction has been developed whichprevents any unwanted crushing or crimping of interconnecting wallmember 95. In accordance with the present invention, the interiorsurface of interconnecting wall member 95 is arcuately rounded, formingpin receiving zone 96. The construction of each clamp member 90 iscompleted by positioning pivot pin 97 in pin receiving zone 96 of wallmember 95, and securely maintaining pivot pin 97 in the preciselydesired position by mounting securing rod 98 through apertures formed inwall 95 and pin 97. In this way, pivot pin 97 is securely retained incontacting engagement with wall member 95, imparting thereto the desiredresistance force for preventing crushing or bending of wall member 95,while enhancing the inherent spring force provided by wall member 95.

As is evident from the foregoing detailed discussion, by securelymounting pivot pin 97 in pin receiving zone 96 of wall member 95, wallmember 95 is incapable of being crushed or bent by the application ofcompressive forces thereto. In addition, the inherent spring forceprovided by wall member 95 to jaws 91 and 92 is enhanced and increased.As a result, the construction provided by this embodiment of the presentinvention clearly establishes an open clamping jaw construction forclamp assembly 60 which completely eliminates all of the prior artdifficulties and drawbacks, and provides a clamp assembly 60 which iscapable of being used with complete assurance that failure of the clampassembly during its use cannot occur.

In FIG. 10, a further alternate embodiment of clamp assembly 60 isshown. In this embodiment, clamping member 90 is employed andconstructed in the manner detailed above. However, in constructing thisembodiment of clamp assembly 60, only one clamp member 90 is used, withrod receiving head 99 being formed at one end of elongated shaft 100,which is threadedly engaged in control plate 93 of clamp member 90. Inaddition, a cooperating rod receiving and securing member 101 is mountedabout shaft 100 in cooperative association with head 99.

Using this construction, any desired rod having the proper diameter isinserted through aperture 102 formed in head 99 and secured therein byV-shaped receiving zone 1002 formed in receiving/securing member 101.The secure, threadedly, affixed interengagement of these components areprovided by employing collar 103, which comprises a head 104 and handle105 and is constructed for threaded interengagement with the terminatingend of shaft 100. As result, by rotationally moving handle 105 or head104, the secure clamping affixation of this embodiment of clamp assembly60 is achieved.

Typically, the components detailed above for achieving external fixationbone stabilizing frame system 20 are employed in constructing framesystems for larger bones. Often times, these bones are weight bearingand must be capable of withstanding substantial stress imposed thereon.However, in addition to the repair and stabilization of larger bonesstructures, smaller bone fragments and elements must also be capable ofbeing supported by an external fixation stabilizing frame system 20.

In this regard, broken or damaged fingers, jaws, wrists, and the likeare examples of areas which require a substantially smaller, lighter,and more delicate external fixation frame system. By referring to FIGS.15-22, along with the following detailed disclosure, the constructionand operation of the preferred component for such an external fixationframe system of the present invention can best be understood.

In FIG. 15, one typical application for employing the smaller componentsof the frame system of the present invention is depicted for holding andstabilizing small broken bones, such as are found in the hand, fingersand wrist. As depicted, one application of employing the externalfixation, bone stabilizing frame system 20 of the present invention issetting a broken or fractured finger bone.

In this regard, the first step in stabilizing a broken or fracturedfinger is the mounting of at least one anchor pin 110 on one side of thebreak or fracture, and mounting at least one additional anchor pin 111on the opposite side of the brake or fracture. In each instance, theanchor pins arc securely affixed directly into the bone of the finger,extending outwardly therefrom. As is well-known in the industry, in anysituation where soft tissue or opened wounds are present, along with abroken or fractured bone, surrounding of the broken bone with a cast orsplint is not possible. Consequently, external fixation frame assembliesare required.

Using the outwardly extending anchor pins 110 and 111, frame system 20of the present invention is created in order to form the required bonestabilizing frame system for maintaining the broken finger bones in theprecisely desired, aligned and engaged position to promote completehealing. In forming the desired frame system 20, two separate andindependent pin clamping/mounting members 115 are employed. As depicted,each pin clamping/mounting member 115 is affixed to one of the anchorpins and then interconnected with each other by clamp assemblies 60 andstabilizing rod 61.

In order to best understand the construction and operation of pinclamping/mounting member 115, reference should be made to the followingdetailed description along with FIGS. 16-22. By referring to theseFigures and the following detailed disclosure, the unique constructionand operational details of pin clamping/mounting member 115 of thepresent invention can best be understood.

As shown in FIGS. 16, 17, and 18, pin clamping/mounting member 115 mayincorporate one or two connecting rods 31, with one or two connectingrods 31 being mounted at opposite ends or substantially mid-way alongthe length of mounting member 115. Regardless of the position or numberof connecting rods 31 mounted to pin clamping/mounting member 115, theoverall construction of clamping/mounting member 115 is substantiallyidentical. In order to best understand this construction, referenceshould be made to FIGS. 16, 17, and 18, wherein these alternateembodiments are depicted and fully detailed below.

In the preferred construction, pin clamping/mounting member 115incorporates housing 116 in which are formed two separate andindependent pin receiving cavities or apertures 117 and 118, extendingfrom the top surface of housing 116 through to the bottom surfacethereof. In addition, as is more fully detailed below, each pinreceiving cavity 117 and 118 preferably comprise a generally rectangularor square cross-sectional shape.

Furthermore, a clamping screw receiving cavity 120 is formed adjacentpin-receiving cavities 117 and 118 also extending from the top to thebottom surface of housing 116. In the preferred construction, clampingscrew receiving cavity 120 comprises an upper enlarged screw receivingzone 125 and a lower zone 126 which comprises a screw threadconfiguration. In addition, the axis of each pin-receiving cavity 117and 118 as well as the axis of screw receiving cavity 120 are all formedsubstantially parallel to each other.

Finally, the construction of housing 116 is completed by forming anenlarged interior slot 121 in one side wall of housing 116, with slot121 dimensioned for receiving and retaining clamping wedge 122. Asclearly shown in FIGS. 16 and 17, slot 121 extends through screwreceiving cavity 120, effectively forming upper zone 125 and lower zone126.

In the preferred embodiment, clamping wedge 122 comprises a generallyrectangular-shaped bar 135 incorporating generally parallel sides 136and 137. Side 136 incorporates an arcuately curved zone 138 which iscentrally disposed thereon and incorporates a sloping or beveled surface142. In addition, side 137 incorporates two arcuately curved zones 139and 140 formed at opposite ends of side 137, with a substantiallystraight, flat, intermediate zone 141 extending therebetween andpositioned forward of curved zones 139 and 140. As detailed below, byemploying this construction, secure abutting, contacting engagement ofanchor pins of any desired diameter, or even different diameters, arecapable of being securely engaged and clampingly retained by member 115.

The overall construction of pin clamping/mounting member 115 iscompleted by providing wedge clamping screw 123, which is constructedfor telescopic insertion and secure retention within cavity 120. In thepreferred construction, wedge clamping screw 123 comprises substantiallycircular-shaped head 128 with shaft 129 extending therefrom. Inaddition, beveled or sloping section 130 extends between head 128 andshaft 129, with the construction of wedge clamping screw 123 beingcompleted by forming threaded portion 131 along the distal end of shaft129. By employing this construction, once wedge damping screw 123 istelescopically inserted into screw receiving cavity 120, threadedportion 131 matingly engages with threaded zone 126, while head 128 ofscrew 123 is able to pass through upper zone 125.

In FIGS. 19-22, the embodiment of pin clamping/mounting member 115 ofFIG. 16 is depicted in detail, showing member 115 in use, securelyclamping and engaging two anchor pins having different diameters. As isevident from a review of these Figures, pin clamping/mounting member 115is capable of secure, clamping interengagement with small, thin ornarrow anchor pins, as commonly employed with smaller and more delicatebone members. In addition, regardless of the diameter of the smallanchor pins that are employed for securing the more delicate bonefragments, pin clamping/mounting member 115 is capable of secureclamping interengagement therewith , even in those instances whereanchor pins of different diameters are required to be secured by asingle pin clamping/mounting member 115.

When employing the present invention, once anchor pins 110 and/or 111are passed through pin-receiving apertures 117 and 118, member 115 isquickly and easily securely clamped therewith by arcuately rotatingwedge clamping screw 123. Once threaded portion 131 of wedge clampingscrew 123 is threadedly engaged in lower zone 126, rotational movementof screw 123 in a first direction advances screw 123 downwardly, causinghead portion 128 to enter receiving zone 125 of cavity 120.

As screw 123 continues to be moved in this downward direction, slopingor beveled section 130 of screw 123 is brought into controlled,contacting engagement with beveled surface 142 of arcuately curvedsection 138 of clamping wedge 122. As a result of this contact,controlled movement of clamping wedge 122 is provided by screw 123,causing wedge 122 to advance in slot 121 towards anchor pins 110 and 111mounted in receiving cavities 117 and 118.

As the rotation of screw 123 continues, movement of clamping wedge 122also continues until curved zones 139 and 140 are brought into abutting,contacting engagement with the anchor pins mounted in receiving cavities117 and 118. Once secure, abutting, contacting, clamping interengagementbetween wedge 122 and anchor pins 110 and 111 is attained, the rotationof screw 123 is halted.

In addition to providing the controlled advance of clamping wedge 122into secure, abutting, clamping engagement with anchor pins 110 and 111mounted in receiving cavities 117 and 118, the construction of clampingwedge 122 also allows arcuate pivoting movement of clamping wedge 122relative to slot 121. As a result, anchor pins having differentdiameters are capable of being securely clamped in a single member 115,with complete assurance that both anchor pins are securely, clampinglyinterengaged therewith.

In addition, this construction of pin clamping/mounting member 115 alsoenables engagement with single anchor pins mounted in either receivingcavity 117 or 118. In this way, regardless of the diameter of the anchorpins that are present, or the absence of one anchor pin, secure, locked,clamped engagement of the anchor pins as desired by the surgeon iscapable of being achieved quickly and easily.

A further feature provided by the present invention is the ability tosecurely affix any desired anchor pins in either one or both pinreceiving cavities 117 and 118, in a manner which provides secure,clamped interengagement of the anchor pin on three separate andindependent sides thereof. As detailed above, pin receiving cavities 117and 118 are preferably formed in a generally rectangular orsquare-shaped configuration.

As a result, any anchor pin positioned in pin receiving cavities 117and/or 118 is forced to enter a corner of the rectangular orsquare-shaped clamping surface thereof as wedge 122 contacts a portionof the anchor pin. Once fully secured therein, the anchor pin contactsclamping wedge 122 on one portion or surface thereof, as well as twowalls of pin receiving cavity 117 and 118 on two additional portions orsurfaces thereof. As a result, positive secure, clamped engagement ofany desired anchor pin in cavities 117 and 118 is obtained on threeseparate portions or sides by employing pin clamping/mounting member 115of the present invention.

As shown in FIG. 15, the broken parts of the finger bone are secured andmaintained in the desired position for healing by securelyinterconnecting two pin clamping/mounting members 115 to each otherusing clamps 60 and stabilizing rod 61. Once this frame assembly iscompleted, the two components of the finger bone are securely mounted toeach other in abutting, contacting, slip-free engagement in order toenable complete healing to be achieved.

In forming frame-assembly 20, clamp assemblies 60 are affixed to eachconnecting rod 31 of each pin clamping/mounting member 115, while alsosecurely affixing a portion of stabilizing rod 61 to each clamp assembly60. In achieving this result, in accordance with the present invention,clamp assemblies 60 are preferably constructed in the manner depicted inFIGS. 23 and 24.

Although the clamp assembly constructions detailed above could beemployed in this embodiment of the present invention, due to theextremely small size requirements imposed upon these components, theconstruction of clamp assembly 60 in the manner detailed above for theframe assemblies employed with the larger bones has been found to bedifficult to achieve economically. Consequently, any alternateconstruction is preferred and the preferred construction for clampassemblies 60 employed in constructing frame assembly 20 of the presentinvention for use with the smaller bone elements is depicted in FIGS. 23and 24, and fully detailed below.

In this embodiment, clamp assembly 60 preferably comprises two separateand independent clamp members 150 mounted in a vertically stacked array,as detailed above in the alternate embodiments of clamp assemblies 60.In this embodiment, each clamp member 150 comprises separate andindependent clamping jaws 151 and 152 for providing easy entry therein.

Furthermore, each clamp member 150 comprises a movement control plate153 which is interconnected with jaw 151 and a movement control plate154 which is interconnected with jaw 152. Movement control plates 153and 154 are positioned in juxtaposed, spaced, vertically aligned,cooperating relationship with each other, enabling clamping jaws 151 and152 to operate in the desired manner.

In order to provide clamping jaws 151 and 152 with the desired,integrated, spring biasing force, each clamp member 150 also comprisesan interconnecting wall member 155 which extends between movementcontrol plates 153 and 154 on the side thereof opposite clamping jaws151 and 152. In this way, an integrated spring force is provided toclamping jaws 151 and 152 which tend to open jaws 151 and 152, unlesscounteracted by a closing or clamping force.

The remainder of the construction of clamp member 150 is substantiallyequivalent to the construction of clamp assembly 60 detailed above. Inthis regard, screw receiving cavities 68 are formed in movement controlplates 153 and 154, with threaded zones being formed in cavities 68 ofeach control plate 153, while a smooth receiving zone is formed incavity 68 of each control plate 154. In addition, if desired, the topsurface of each control plate 154 may comprise a circular array of teethand grooves, for providing the desired mating, interengagement andarcuate rotational movement of each clamp member 150 relative to theother clamp member 150.

In addition, clamping control screw 70 is telescopically insertedthrough screw receiving cavities 68 of each movement control plate 153and 154, with threaded zone 71 of screw 70 being engaged in cavity 68 ofthe lowermost control plate 153. In addition, with clamping controlscrew 70 incorporating head 72, shank portion 74, and washer 75, asdescribed above, any arcuate rotation of control screw 70 in a firstdirection causes jaws 151 and 152 of each clamping member 150 to advancetowards each other, securely engaging and lockingly retaining any rodmember inserted therebetween. In addition, as detailed above, handle 76may be mounted, if desired, to head 72 of screw 70 in order to enableprecise, controlled, rotational movement of screw 70.

In this embodiment of the present invention, unwanted crushing orcrimping of interconnected wall member 155 is prevented by forminginterior wall 156 of wall member 155 with a longitudinally extending,enlarged, generally oval or rectangular cross-sectional shape formedalong the juncture between wall member 155 and movement control plates153 and 154. As clearly depicted in FIGS. 23 and 24, the juncturebetween wall member 155 and movement control plate 153 comprises asmoothly rounded, arcuately curved zone 157 extending the entire widthof wall member 155 at the juncture between these two components.Similarly, an arcuately curved, smoothly rounded zone 158 is formed atthe juncture between wall member 155 and movement control plate 154. Asa result, the generally oval or rectangular shaped configuration isobtained between these elements along interior wall 156.

By employing this construction, a resisted force imparted to wall member155, preventing crushing or bending of wall member 155, while enhancingthe spring force provided thereby. As result, the desirable qualitiesfor clamp member 150 are obtained and unwanted crushing or bending ofwall member 155 is prevented.

It will thus be seen that the objects set forth above, among those madeapparent from the preceding description, are efficiently attained and,since certain changes may be made in the above article without departingfrom the scope of the invention, it is intended that all mattercontained in the above description or shown in the accompanying drawingsshall be interpreted as illustrative and not in a limiting sense.

It is also to be understood that the following claims arc intended tocover all of the generic and specific features of the invention hereindescribed, and all statements of the scope of the invention which, as amatter of language, might be said to fall therebetween.

1. A kit for assembly into an adjustable bone stabilizing frame comprising: (a) a plurality of pin clamping and mounting members comprising: (i) a plurality of pin receiving cavities constructed for receiving and securely clamping a bone-mounted pin therein, (ii) a clamping plate adapted to be movably mounted in the pin clamping and mounting member in cooperating relationship with the pin receiving cavity, (iii) a wedge member adapted to be movably mounted in the pin clamping and mounting member and adapted to be controllably engaged with the clamping plate for controlling the movement thereof into engagement with the bone-mounted pin mounted in one of the pin receiving cavities; and (iv) at least one rod adapted to be mounted to the pin clamping and mounting member so as to extend therefrom; (b) at least one stabilizing rod adapted to be positioned in cooperating relationship with the pin clamping and mounting members, and (c) clamp assemblies adapted to be securely mounted to the rods of the pin clamping and mounting member and the stabilizing rod for forming the desired securely engaged, external bone stabilizing frame assembly.
 2. (canceled)
 3. The kit of claim 1, wherein said plurality of pin receiving cavities are defined as being substantially parallel to each other and extending through the pin clamping and mounting member.
 4. The kit of claim 3, wherein each pin clamping and mounting member comprises a clamping plate receiving cavity formed therein and extending substantially perpendicular to the axis of the pin receiving cavity, whereby movement of the clamping plate in the plate receiving cavity causes frictional engagement of the clamping plate with the bone-mounted pin when said pin is positioned in the pin receiving cavity.
 5. The kit of claim 4, wherein said pin receiving cavity comprises a cross-sectional shape selected from the group consisting of squares and rectangles, each having a plurality of adjacent surfaces, thereby enabling bone-mounted pins of different diameters to be secure therein.
 6. The kit of claim 5, wherein the clamping plate comprises a pin engaging surface controllably moved by the wedge member for bringing the pin engaging surface into contact with the pin mounted in the receiving cavity and securely locking the pin between the engaging face of the clamping plate and the adjacent surfaces of the pin receiving cavity, whereby pins of different diameters are easily secured thereby. 